PERL5161DELTA(1) Perl Programmers Reference Guide PERL5161DELTA(1)
NAME
perl5161delta - what is new for perl v5.16.1
DESCRIPTION
This document describes differences between the 5.16.0 release and the
5.16.1 release.
If you are upgrading from an earlier release such as 5.14.0, first read
perl5160delta, which describes differences between 5.14.0 and 5.16.0.
Security
an off-by-two error in Scalar-List-Util has been fixed
The bugfix was in Scalar-List-Util 1.23_04, and perl 5.16.1 includes
Scalar-List-Util 1.25.
Incompatible Changes
There are no changes intentionally incompatible with 5.16.0 If any
exist, they are bugs, and we request that you submit a report. See
"Reporting Bugs" below.
Modules and Pragmata
Updated Modules and Pragmata
• Scalar::Util and List::Util have been upgraded from version 1.23 to
version 1.25.
• B::Deparse has been updated from version 1.14 to 1.14_01. An
"uninitialized" warning emitted by B::Deparse has been squashed
[perl #113464].
Configuration and Compilation
• Building perl with some Windows compilers used to fail due to a
problem with miniperl's "glob" operator (which uses the "perlglob"
program) deleting the PATH environment variable [perl #113798].
Platform Support
Platform-Specific Notes
VMS All C header files from the top-level directory of the distribution
are now installed on VMS, providing consistency with a long-standing
practice on other platforms. Previously only a subset were
installed, which broke non-core extension builds for extensions that
depended on the missing include files.
Selected Bug Fixes
• A regression introduced in Perl v5.16.0 involving
"tr/SEARCHLIST/REPLACEMENTLIST/" has been fixed. Only the first
instance is supposed to be meaningful if a character appears more
than once in "SEARCHLIST". Under some circumstances, the final
instance was overriding all earlier ones. [perl #113584]
• "B::COP::stashlen" has been added. This provides access to an
internal field added in perl 5.16 under threaded builds. It was
broken at the last minute before 5.16 was released [perl #113034].
• The re pragma will no longer clobber $_. [perl #113750]
• Unicode 6.1 published an incorrect alias for one of the
Canonical_Combining_Class property's values (which range between 0
and 254). The alias "CCC133" should have been "CCC132". Perl now
overrides the data file furnished by Unicode to give the correct
value.
• Duplicating scalar filehandles works again. [perl #113764]
• Under threaded perls, a runtime code block in a regular expression
could corrupt the package name stored in the op tree, resulting in
bad reads in "caller", and possibly crashes [perl #113060].
• For efficiency's sake, many operators and built-in functions return
the same scalar each time. Lvalue subroutines and subroutines in
the CORE:: namespace were allowing this implementation detail to
leak through. "print &CORE::uc("a"), &CORE::uc("b")" used to print
"BB". The same thing would happen with an lvalue subroutine
returning the return value of "uc". Now the value is copied in such
cases [perl #113044].
• "__SUB__" now works in special blocks ("BEGIN", "END", etc.).
• Formats that reference lexical variables from outside no longer
result in crashes.
Known Problems
There are no new known problems, but consult "Known Problems" in
perl5160delta to see those identified in the 5.16.0 release.
Acknowledgements
Perl 5.16.1 represents approximately 2 months of development since Perl
5.16.0 and contains approximately 14,000 lines of changes across 96
files from 8 authors.
Perl continues to flourish into its third decade thanks to a vibrant
community of users and developers. The following people are known to
have contributed the improvements that became Perl 5.16.1:
Chris 'BinGOs' Williams, Craig A. Berry, Father Chrysostomos, Karl
Williamson, Paul Johnson, Reini Urban, Ricardo Signes, Tony Cook.
The list above is almost certainly incomplete as it is automatically
generated from version control history. In particular, it does not
include the names of the (very much appreciated) contributors who
reported issues to the Perl bug tracker.
Many of the changes included in this version originated in the CPAN
modules included in Perl's core. We're grateful to the entire CPAN
community for helping Perl to flourish.
For a more complete list of all of Perl's historical contributors,
please see the AUTHORS file in the Perl source distribution.
Reporting Bugs
If you find what you think is a bug, you might check the articles
recently posted to the comp.lang.perl.misc newsgroup and the perl bug
database at http://rt.perl.org/perlbug/ . There may also be information
at http://www.perl.org/ , the Perl Home Page.
If you believe you have an unreported bug, please run the perlbug
program included with your release. Be sure to trim your bug down to a
tiny but sufficient test case. Your bug report, along with the output
of "perl -V", will be sent off to perlbug@perl.org to be analysed by the
Perl porting team.
If the bug you are reporting has security implications, which make it
inappropriate to send to a publicly archived mailing list, then please
send it to perl5-security-report@perl.org. This points to a closed
subscription unarchived mailing list, which includes all the core
committers, who will be able to help assess the impact of issues, figure
out a resolution, and help co-ordinate the release of patches to
mitigate or fix the problem across all platforms on which Perl is
supported. Please only use this address for security issues in the Perl
core, not for modules independently distributed on CPAN.
SEE ALSO
The Changes file for an explanation of how to view exhaustive details on
what changed.
The INSTALL file for how to build Perl.
The README file for general stuff.
The Artistic and Copying files for copyright information.
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